The present invention relates to a stereo image generating and displaying method and apparatus and, more particularly, to a stereo image generating and displaying method and apparatus which interpret geometrical figure data showing font types, plane figures, solid shapes, and so on, and attributes data representing color and texture, for example, and environmental data, such as data of illuminating light and projection, calculate and generate a few to several frames of new stereo images in a second, and modify displayed stereo images as soon as new stereo images are generated, capable of processing at real time.
Conventionally, no matter where on a display screen a viewer is watching, a stereo image generating and displaying apparatus of a real-time processing type for displaying a moving picture generates an entire image to be displayed on the display screen by using a single image generating algorithm.
Generally, in a stereo image generating and displaying apparatus of real-time processing type, speed to generate images to be displayed on a display screen has priority over quality of the images. In order to process images at real time, it is necessary to decrease processing load on the apparatus by simplifying an image generating algorithm, for instance.
However, when conventional method for simplifying an image generating algorithm is used, quality of entire images uniformly decreases, which makes a viewer clearly notice a drop of image quality.
To avoid the aforesaid problem, it has been necessary to use an expensive high speed computer which is exclusively used for image generation in order to generate images of moderate quality at real time. Even though an expensive high speed computer is used, there are many cases where satisfactory image quality cannot be achieved.
When a viewer watches an object with both right and left eyes, the eyes move so as to focus corresponding points in an image seen by the right eye and in an image seen by the left eye. This eye movement is called xe2x80x9cconvergence eye-movementxe2x80x9d. Accordingly, the viewer perceives the object as a single solid image.
In contrast, other objects which are placed in either closer or farther positions than a focusing position of right and left eyes, e.g., an object B shown in FIG. 23, are seen as vague overlapped images, since binocular parallaxes to these objects are different from that to the object at the focusing position.
We daily experience this phenomenon although we do not usually conceive the phenomenon. In geometrical explanation, binocular parallaxes to points which are on a circumference (Vieth-Muller""s holopter) that passes through positions of right and left eyes and a focus point of the eyes are same, as shown in FIG. 24. Therefore, images of an object, seen by right and left eyes, on the circumference look focused, thus perceived as a single image. Actually, there are some allowance area for human eyes to see an object as a unified single, image, and the area is called xe2x80x9cPanum""s fusional areaxe2x80x9d (Toyohiko Hatada, xe2x80x9cPsychology to See a Stereoscopic Imagexe2x80x9d, Vol. 20, No. 1, pp. 27-38, 1988).
The present invention has been made in consideration of the above situation, and has as its object to generate and display stereo images of better quality while keeping image processing speed by reducing calculation load for generating each stereo image.
According to the present invention, the foregoing object is attained by providing a method for generating stereo images from figure data of objects, the method comprising: a first determination step of determining whether or not an object to be rendered in the stereo images is in a specific area which is determined by eye characteristics, on the basis of a focus point and line-of-sight directions of right and left eyes; and a generating step of generating stereo images based on the figure in a first image generating method when the object to be rendered in the stereo images is inside of the specific area, and in a second image generating method when the object to be rendered in the stereo images is outside of the specific area.
With the aforesaid method, an image can be processed by using different kinds of image generating algorithms and parameters for a fusional area which is decided by characteristics of the eyes and for other areas. Therefore, it is possible to generate stereo images of better quality while keeping image processing speed by reducing calculation load for generating each stereo image.
It is another object of the present invention to provide a method for generating stereo images from figure data of objects and displaying the generated stereo images, the method comprising: an operation step of obtaining a visual acuity factor of right and left eyes of a viewer for the figure data of each object on the basis of focus point and line-of-sight directions of the right and left eyes of the viewer; a generating step of generating stereo images of first and second objects by applying different image generating methods to the first and second objects whose visual acuity factor, obtained at the operation step, is different from each other; and a displaying step of displaying the stereo images generated at the generating step.
Still another object of the present invention is to provide a method for generating stereo images from figure data of objects and displaying the generated stereo images, the method comprising: an operation step of obtaining a visual acuity factor of right and left eyes of a viewer for the figure data of each object on the basis of focus point and line-of-sight directions of the right and left eyes of the viewer; a determination step of determining a required precision for each object to be rendered in stereo images on the basis of the visual acuity factor obtained at the operation step; a generating step of generating stereo images of the objects by changing parameters for an image generating method to be applied to figure data of each object on the basis of the required precision determined at the determining step; and a displaying step of displaying the stereo images generated at the generating step.
According to the aforesaid methods, resolution of each of plurality of parts which consist the stereo images can be flexibly adjusted in accordance with a visual acuity factor. More specifically, it is possible to choose parameters to be used in an image generating method selected in accordance with the visual acuity factor, thus calculation load for generating each stereo image is reduced and stereo images of better quality can be generated and displayed.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.